1. Field of the Invention
The field of this invention is power tools, and more particularly reciprocating saws.
2. Description of Related Art
Reciprocating saws have long been offered by power tool manufacturers and are especially useful to tradesmen in the building industry. Tradesmen such as carpenters, plumbers, electricians, HVAC mechanics, and central vacuuming system installers use reciprocating saws to make cuts in wood, plastic, and metal materials while accomplishing an infinite variety of tasks. The ample power, durability, and ease of use which are characteristic of reciprocating saws make them a versatile tool well suited to accomplish many different jobs.
Despite the versatility already possessed by reciprocating saws, the reciprocating saw is not well suited for every task a tradesmen faces. Traditional reciprocating saws are often not useful where only limited maneuvering space is available around the workpiece to be cut. Traditional reciprocating saws are relatively long tools. The saw blade, reciprocating mechanism, motor and handle are typically positioned longitudinally in-line with one anotherxe2x80x94the Cordless Tiger Saw from Porter-Cable, described in U.S. patent application Ser. No. 09/627,780, being a notable and rare departure from this configuration. Because of their length, traditional reciprocating saws are difficult to use in cramped quarters. As one example, traditional reciprocating saws are difficult to use inside of a cabinet. Given the limited maneuvering space inside the cabinet and a relatively long saw, the user often cannot maneuver the saw into position so that the blade can move along the cutting path. When this is the case, then resort must be made to another power tool, or to a hand tool. For another example, plumbers and HVAC mechanics often need to make cuts in floor joists which are spaced 16 inches on center. The length of most traditional reciprocating saws greatly hampers these cuts because the saw cannot fit perpendicularly between the joists. As a final example, plumbers sometimes need to cut a pipe even with or below a surface. With a traditional reciprocating saw, a plumber would be forced to excavate a large hole below the surface in order to position the saw perpendicular to the pipe with the saw blade adjacent the cut. The excavation of such a hole is time consuming and costly for the plumber. These examples show how the length of traditional reciprocating saws can hamper or even prevent its use for some tasks.
The configuration of traditional reciprocating saws can sometimes make their use awkward and uncomfortable. The configuration of a traditional reciprocating saw does not provide adequate leverage to control fine cutting by the saw blade. Because the handle is in line with the reciprocating motion of the saw blade, only a small moment can be developed to help turn the saw blade during a cut. Partially for this reason, it is often difficult to make small radius cuts or to closely follow a fine cutting line with a traditional reciprocating saw.
The lack of adjustability of traditional reciprocating saws can impede their use. A traditional reciprocating saw only cuts when the saw blade is moved against the workpiece in one direction. Because the saw has only one direction of cut and no provision to adjust the configuration of the saw blade relative to the body and handle of the saw, the user must sometimes hold the saw in an awkward and uncomfortable position. Further, some cuts with a traditional reciprocating saw are prevented because of obstacles which block access to the workpiece even when maneuvering space is otherwise available. If the reciprocating saw were capable of xe2x80x9cbendingxe2x80x9d around the obstacle, the cut could be made.
Several manufacturers and individuals have suggested modifications to the traditional reciprocating saw to overcome some of the drawbacks mentioned above. Notable among these are the inventions disclosed in U.S. Pat. No. 6,138,364 to Jeffrey Schmitz, U.S. Pat. No. 5,940,977 to Robert Moores, Jr., and U.S. Pat. No. 3,585,719 to Stanley Kivela. None, however, provide the versatility of the reciprocating saw of the present invention.
The present invention seeks to increase the versatility of a reciprocating saw to perform an even greater number of tasks by permitting adjustment of the reciprocating saw""s configuration. In one embodiment of the adjustable reciprocating saw disclosed herein, the saw blade is continuously adjustable about two transverse rotational axes. This allows the saw blade to be adjusted to a wide range of positions relative to the saw. This adjustability can be highly beneficial when cutting in confined spaces and with obstacles, when closely following cutting lines, and when cutting small radius curves, among other situations often faced by tradesmen. The present invention also seeks to maintain or even improve the compactness, power, and durability of reciprocating saws.
In one embodiment of the invention, a reciprocating shaft and bearing combination for a reciprocating saw comprises a bearing mounted to the saw, a reciprocating shaft having a blade holder at a first end thereof for holding a saw blade, the reciprocating shaft having a reciprocating motion relative to the bearing defining a reciprocating motion axis, the reciprocating shaft also having a bore formed in a second end opposite the first end, and the bore being formed parallel to the reciprocating motion axis and a first end of the bearing being positioned inside the bore. The combination further comprises a first bearing surface formed on the bearing, and a second bearing surface formed on the bore. The first bearing surface supports the second bearing surface for sliding movement there between.
In another embodiment of the invention, a reciprocating saw comprises a saw blade extending from the saw and having a reciprocating motion, a shoe for bearing against a workpiece, the shoe extending from the saw adjacent the saw blade, the shoe mounted to a post slidably received in a bore in the saw, and a locking mechanism rotatably mounted to the saw for locking the post to the saw, the locking mechanism being rotatable with respect to the saw about a rotational axis, the locking mechanism having at least one protrusion at an axial end thereof extending axially away from the locking mechanism. In a first rotational position, the at least one protrusion engages a detent in the post so that the post is locked relative to the saw, and in a second rotational position the at least one protrusion does not engage the detent so that the post can slide in the bore relative to the saw blade.
In another embodiment of the invention, a reciprocating saw comprises a rotary motor, a reciprocating mechanism for converting rotary motion of the rotary motor into reciprocating motion, a stationary housing portion, a scroll housing portion rotatably mounted to the stationary housing portion, and a reciprocating shaft having a reciprocating motion relative to the scroll housing portion, the reciprocating motion being driven by the reciprocating mechanism and defining a reciprocating motion axis. The reciprocating shaft comprises a first end extending from the scroll housing portion, and a blade holder for holding a saw blade, the blade holder being mounted on the first end. The scroll housing portion rotates relative to the stationary housing portion and the reciprocating mechanism about a first axis of rotation which is substantially parallel to the reciprocating motion axis, the rotation of the scroll housing portion causing the saw blade to rotate in unison therewith.
In another embodiment of the invention, a power tool comprises a stationary housing portion and a movable housing portion mounted to the stationary housing portion for rotation about an axis of rotation. One of the stationary housing portion or the movable housing portion has a radial flange centered on the axis of rotation and extending at least part way around the axis of rotation, and the other of the stationary housing portion or the movable housing portion has one or more locking pieces detachably mounted thereon. The one or more locking pieces each engage the flange thereby blocking relative axial movement of the stationary housing portion away from the movable housing portion while permitting relative rotational movement of the stationary housing portion and the movable housing portion. When the one or more locking pieces are detached from the other of the stationary housing portion or the movable housing portion, the stationary housing portion and the movable housing portion can be disassembled from one another.
In another embodiment, a method of fastening first and second housing portions of a power tool where the first and second housing portions rotate relative to one another comprises the steps of assembling the first and second housing portions together so that bearing surfaces formed on each are engaged with one another, and mounting one or more locking pieces onto one of the first or second housing portions without the use of separate removable fasteners so that the locking pieces engage a surface formed on the other of the first or second housing portions thereby permitting relative rotational movement between the first and second housing portions about an axis of rotation and blocking relative axially movement of the first housing portion away from the second housing portion.
In another embodiment, a saw comprises a reciprocating mechanism for producing a reciprocating motion, and a reciprocating shaft having a reciprocating motion driven by the reciprocating mechanism. The reciprocating shaft comprises a blade holder proximate a first end, a first flange integrally formed with the reciprocating shaft proximate a second end opposite the first end. A second flange is selectively detachably mounted to the reciprocating shaft. A portion of the reciprocating mechanism alternately pushes against the first and second flanges when the reciprocating mechanism is driving the reciprocating shaft, and the first and second flanges cooperate to trap there between the portion of the reciprocating mechanism.
In another embodiment, a saw comprises a reciprocating shaft having a reciprocating motion, the reciprocating shaft comprising a blade holder on one end thereof, and a reciprocating mechanism for driving the reciprocating shaft in its reciprocating motion, the reciprocating mechanism comprising a yoke. One of the reciprocating shaft or the yoke has a first locking flange integrally formed therewith, and a second locking flange selectively detachably mounted thereto. The first locking flange and the second locking flange alternately engage a portion of the other of the reciprocating shaft or the yoke to transfer a force there between thereby driving the reciprocating shaft in its reciprocating motion, and the first and second locking flanges cooperate to trap there between the portion of the other of the reciprocating shaft or the yoke.
In another embodiment, a power tool comprises a stationary housing portion, a movable housing portion mounted to the stationary housing portion for rotation about an axis of rotation, and a locking system for preventing rotation of the movable housing portion relative to the stationary housing portion. The locking system comprises a plurality of angularly spaced detents radially formed at least part way around the axis of rotation on one of the stationary housing portion or the movable housing portion, and a locking mechanism mounted to the other of the stationary housing portion or the movable housing portion to be movable between first and second positions wherein when in the first position, the locking mechanism engages one of the detents, and in a second position, the locking mechanism bypasses at least one of the detents allowing relative rotation between the stationary housing portion and the movable housing portion. The locking mechanism is actuated to move between its first and second position by the hand of a user of the power tool.
In another embodiment, a saw comprises a first housing portion having a handle portion with a trigger switch for actuating the saw, a second housing portion mounted to the first housing portion, and a reciprocating shaft extending from the second housing portion, the reciprocating shaft having a blade holder with a saw blade mounted thereon, and the reciprocating shaft having a reciprocating motion defining a reciprocating motion axis. The saw blade is rotatable relative to the first housing portion about a first rotational axis generally perpendicular to the reciprocating motion axis, and the saw blade is continuously rotatable relative to the first housing portion about a second rotational axis generally parallel with the reciprocating motion axis.
In another embodiment, a reciprocating saw comprises a first housing having a handle portion and a motor portion for mounting a rotary electric motor, a second housing rotationally mounted to the first housing, a third housing rotationally mounted to the second housing, and a reciprocating shaft extending out from the third housing, the reciprocating shaft having a reciprocating motion defining a reciprocating motion axis. The second housing is rotationally mounted to the first housing about a first axis of rotation substantially perpendicular to the reciprocating motion axis, and the third housing is rotationally mounted to the second housing about a second axis of rotation substantially parallel to the reciprocating motion axis.
In another embodiment, a saw comprises a first housing portion having a handle portion with a trigger switch for actuating the saw, a second housing portion mounted to the first housing portion, and a reciprocating shaft extending from the second housing portion, the reciprocating shaft having a blade holder with a saw blade mounted thereon, and the reciprocating shaft having a reciprocating motion defining a reciprocating motion axis. The saw blade is rotatable relative to the first housing portion about a rotational axis generally perpendicular to the reciprocating motion axis when a button mounted on one of the first or second housing portions is depressed.
In another embodiment, a method of adjusting a reciprocating sawxe2x80x94the reciprocating saw comprising a first housing portion having a handle portion with a trigger switch for actuating the saw, a second housing portion mounted to the first housing portion, and a reciprocating shaft extending from the second housing portion, the reciprocating shaft having a blade holder with a saw blade mounted thereon, and the reciprocating shaft having a reciprocating motion defining a reciprocating motion axisxe2x80x94comprises the steps of depressing a button thereby permitting rotation of the saw blade relative to the first housing about a rotational axis generally perpendicular to the reciprocating motion axis, rotating the saw blade about the rotational axis, and releasing the button causing the saw blade to be locked relative to the first housing about the rotational axis.